If you live *miles* away from a dealer, like I do, buy the airhead. Chances are, you'll be able to keep her running and save the expense of mechanic's time. I am very comfortable with going out into the middle of nowhere on the PD now that I've had the transmission rebuilt, the drive shaft reworked, replaced the cables, cleaned all the electrical contacts, tuned the engine, put in a new battery, replaced the alternator rotor, ...... you get the idea. Most everything on an airhead will give you some warning of an impending failure; electronics, on the other hand, just quit.
As the bikes continue to age, the electronics of the oilhead will become more of an issue and its value will continue to go down while the airhead will hold it's value if properly maintained.
One added plus for the airhead: In case of nuclear attack, the airhead will still run.
Can anyone recall the FI failing on an oilhead?
I can't think of any cases that didn't involve someone applying large amounts of current to the frame.